NEUROPATHOLOGY AND THE SCRAPIE-KURU CONNECTION

When their kinship was surmised 35 years ago, scrapie and kuru were li nked mainly by their neuropathologic similarity Most notable were neur onal degeneration and intense astrocytosis with little, if any, inflam mation. Especially eye-catching in kuru were the vacuolated neurons - the histologic hall-mark of scrapie that drew me to the human disease from the start. Because spongiform change in gray matter neuropil is v ariable and usually lacks prominence in both scrapie and kuru, it was not part of the resemblance I saw in them. Amyloid plaques, so charact eristic of kuru, also did not figure in the similarity, for they had n ot yet been reported in scrapie. Despite the uncertainty at the time a bout the pathologic essence of scrapie, the two diseases still looked alike. Their eventual connection - however tenuously held together ini tially by the few likenesses - has survived as a tribute to morphologi c observation. It provided the essential link that helped ensure the k inship a Tasting place in comparative neuropathology.